Push and pull jack



Patented Feb. 11, 1930 y UNITED STATES PATENT OFFICE PUSH AND PULL JACK Application filed February 21, 1927. Serial No. 169,818.

This invention, relatesto improvements in thrust bearings foruse in connection with jacks and therlilre, and has for its object to provide a simple, eiiicientand inexpensive device of this character.

i One ofthe objects of my invention is to j provide means for preserving the life of the contact tipsof the thrust bearings, and to compensate for wear to the end that thescrew forming the main impact surface of the apparatus will not beeasily damaged.

Another object of my invention is to provide a novel thrust bearing for a screw of a jack, especially for a jack designed for heavy duty. For example where `the jack is employed to bend axles of automobiles and the j like, three points of engagement areprovided between the axle and the operable portions ot the jack; two of these points at the l 0 ends of theaxle define the locations for steady fixedly mountedprops while the other point delines the location for a movable pressureinducing part that strains the axle to bend the same or to straighten out bends therein.

'M25 This movable part or jaw of the jack is subject to severe strains and rough usuage `and it is this part that consequently wears, loses its shape or otherwise becomes distored. My invention provides means for preventing the l thrust or pressure inducing part of the jack becoming mashed or broken if not bent.

My invention consists in providing a hardened spur for removable association with the thrust end of the jack screw; this spur is held against displacement in a bore formed `in the axis of the screw; this spur having a pointed projection extending below the screw and it is this pointed projection that comes into contact with the axle or other body to be strained.

With the above and other objects in view my invention consists in the combination, arrangement, and detailsjo construction disclosed in the drawings and specifications, and then more particularly pointed out in the appended claims.

In the drawings, wherein similar reference characters designate similar parts thruj out the respective views,

Figure 1 is a front elevation of a jack showing my invention mounted in position thereupon, v

Figure 2 is an end elevation of a hanger, i

Figure 8 is a top plan view of a screw forming part oit my invention,

Figure 4 is a bottom plan screw,

Figure 5 is a plan detail view of a split retainer ring,

Figure 6 is a side view of the screw show- 60 ing my invention mounted in position thereupon, j

Figure 7 is tragmental detail view of the lower portion or the screw in which my invention is lodged, and

Figure 8 is a front elevation of the `jack shown in Figure l applied to bending a rail or the like.

In the drawings, in which the parts of my invention are shown, a push and pull ack is disclosed, as my invention is designed particularly for use in conjunction with this appliance or apparatus. Thisjack consists of a main frame or support of steel designated 1, and formed centrally with a sleeve 2 inter- 75 nally screw-threaded for the reception in threaded relation of a screw l0 the outer end of which is designated 3. The support l is provided with integral oppositely extending flanges 4L upon which are slidably mounted 90 hangers 21 or the like. The lower active end of the screw is formed with aboss 6, to which may be secured a jaw 9 carrying the hooksA or props 8, as may be desired. A series of rigid pins 7 may radiate from the boss 6 to support chains as hereinafter described.

The jaw 9, whether formed integral upon the screw 10 or whether mounted removably thereupon, carries the thrust bearing which constitutes `my invention. The threads formed upon the screw l0 are designated 3', and may appear at the upper as well as upon the lower end of the screw. 9 designates the nut engaging the screwl() for the purpose of 95 providing an adjustable bearing surface movable relatively to the adjacent end of the screw. V

The upper end of the screw may be formed either round or polygonal as shown in Figview of said ure 3, Where the polygonal portion is designated 20.

The threaded part of the screw is cored out to provide an internal bore 14 for the removable reception of a plug or spur 13; a wear plate 12 is first inserted snugly into bore 14 and pushed in to engage the bottom wall thereof;` then the plug 13 engages this wear plate, so in case of severe strain impressed u on this wear plate by this plug 13, the p ate will be mashed, and may readily be replaced. The plug is formed with a hardened point 14', part of which extends into the bore 14 and part projects therebeneath below the screw 10. In order to hold this lug 13 in position within the bore, the bore ls formed short of its mouth with an annular groove 15; and a split ring 16 split as at 19 is snapped'into the bore 14 until it tits expansively into the annular groove 15; this ring will be made of a diameter to embrace the inner part of the projection or point 14 so as to prevent the plug from becoming displaced from this bore. Therefore the ring will be of a lesser diameter with respect to the portion of the plug immediately above it.

designates a slide block which engages the flange 4 adjustably. Gr a hanger 21 may engage this flange; this hanger being formed with hook-shaped sides 22, 23 engaging over and around the flange 4 oi the jack as shown in Figure 2.V A plate 18 may be removably secured to the head or abutment 9 and may serve to retain the plug 13 within its bore, and in this case this plate will be formed with an opening thru which the point 14 of the plug may project.

By threading the abutment 9 upon the screw the plate 18 is moved along until it engages the point of the plug, which it serves to retain in position.

The ack illustrated in Figure 1 thus includes the screw which carries my thrust bearing. In straightening out axles pipes and heavy bodies the body is designed to be pushed; the chains 24 hook upon the slide members 5, at one end, and are looped opera tively around the ends of the axle A; the slide members being disposed at the ends of the axle, for this purpose. The screw in bearing 2 will be turned so as to be brought with the thrust bearing point 14 upon the bulged portion of the axle centrally of the axle. As the screw continues to turn, of course the plug point 14 straightens out the axle, the chains allowing the ends of the axle to remain fixed. The wear plate 12 takes up the direct thrust of the plug point 14. Without this point, the head 9 of the screw would be mashed, or distorted considerably. Thus my invention relieves the screw from excessive or rapid wear.

In Figure 7 the same jack is shown positioned so as to allow the axle to be bent or strained centrally, as may be desired. Here the hangers 21 replace the chains but occupy the same position on the flange 4. Instead of the thrust bearing engaging the axle centrally, a chain 24 is employed which engages the pins 7 and is also looped around and under the axle A2. Here the screw pulls instead oi pushes the axle and the axle is straightened out again. I do not limit myself to the exactdetails herein shown but cover all changes falling within the range of the appended claims.`

What I. desire to protect and claim is as followsz- 1.v A centering bearing for jacks and the like including a screw formed at its lower end with a bore, a wear plate snugly disposed in said bore and resting against the bottom thereof, a hardened shank snugly litting said bore and having a flat inner side overlapping said wear plate, the outer end of said shank being pointed and projecting below said bore, and means in said bore, interposed between the wall of said bore and said shank and embracing the latter 'for removably posi tioning it within the bore.

2. A centering bearing for jacks and the like consisting of a screw formed at its lower end with a bore, a wear plate secured in said bore and resting against the bottom o said bore, said bore contiguous to its mouth being formed with an annular groove, a hardened spur litting snugly in said bore and having a tapering pointed terminal intersecting the plane of said groove, and a ring pressed so that its perimetral edge is seated in said groove and such that its inner edge embraces the tapering plug to support the same.

3. A centering bearing for jacks and the like consisting of a screw formed at its lower end with a bore, said bore having an annular groove a wear plate secured in said bore, and a spur disposed in said bore and engaging said wear plate, said spur being termed with a hardened pointed projection extending partially into said bore and therebelow, a split ring having a press lit in said annular groove, said pointed projection extending thru so as to be seated by its own weight upon said ring.

In witness whereof he has hereunder set his hand this thirty-lirst day of December,

VILLIAM E. TURLEY. 

